Vital Signs: HIV Diagnosis, Care, and Treatment Among Persons Living with HIV — United States, 2011

Background Infection with human immunodeficiency virus (HIV), if untreated, leads to acquired immunodeficiency syndrome (AIDS) and premature death. However, a continuum of services including HIV testing, HIV medical care, and antiretroviral therapy (ART) can lead to viral suppression, improved health and survival of persons infected with HIV, and prevention of HIV transmission. Methods CDC used data from the National HIV Surveillance System and the Medical Monitoring Project to estimate the percentages of persons living with HIV infection, diagnosed with HIV infection, linked to HIV medical care, engaged in HIV medical care, prescribed ART, and virally suppressed in the United States during 2011. Results In 2011, an estimated 1.2 million persons were living with HIV infection in the United States; an estimated 86% were diagnosed with HIV, 40% were engaged in HIV medical care, 37% were prescribed ART, and 30% achieved viral suppression. The prevalence of viral suppression was significantly lower among persons aged 18–24 years (13%), 25–34 years (23%), and 35–44 years (27%) compared with those aged ≥65 years (37%). Conclusions A comprehensive continuum of services is needed to ensure that all persons living with HIV infection receive the HIV care and treatment needed to achieve viral suppression. Improvements are needed across the HIV care continuum to protect the health of persons living with HIV, reduce HIV transmission, and reach prevention and care goals. Implications for public health practice State and local health departments, community-based organizations, and health care providers play essential roles in improving outcomes on the HIV care continuum that increase survival among persons living with HIV and prevent new HIV infections. The greatest opportunities for increasing the percentage of persons with a suppressed viral load are reducing undiagnosed HIV infections and increasing the percentage of persons living with HIV who are engaged in care.


Introduction
In the United States, an estimated 1.2 million persons are living with human immunodeficiency virus (HIV), a serious infection that, if untreated, leads to illness and premature death. Persons living with HIV who use antiretroviral therapy (ART) and achieve very low levels of the virus (suppressed viral load) can have a nearly normal life expectancy (1) and have very low risk for transmitting HIV to others (2). However, each year in the United States, nearly 50,000 persons become infected with HIV (3). Each step along the HIV care continuum (HIV diagnosis, prompt and sustained HIV medical care, and ART) is essential for achieving a suppressed viral load.
To accelerate progress toward reaching the goals of the National HIV/AIDS Strategy (NHAS), which include reducing new HIV infections, improving health outcomes among persons living with HIV, and reducing HIV-related disparities, the President issued an executive order in July 2013 directing federal agencies to improve outcomes along the HIV care continuum, with the goal of increasing viral suppression among persons living with HIV. This report estimates the number of persons living with HIV who received selected services along the HIV care continuum in the United States and the overall percentage of persons with suppressed viral load.  (5). Numbers are weighted, nationally representative population estimates from a complex sample survey of persons in HIV medical care in the United States. Being engaged in care was defined as having had an HIV medical care visit during the survey's sampling period of January-April 2011. ART was defined as documentation in the medical record of an ART prescription during the 12 months preceding interview. Viral suppression was defined as documentation in the medical record of viral load <200 copies/mL at last viral load test in the 12 months preceding interview. Statistical testing of differences between groups was conducted using the delta method (6).

Findings
In 2011, an estimated 1.2 million persons were living with HIV infection in the United States; an estimated 86% were diagnosed with HIV, 40% were engaged in HIV medical care, 37% were prescribed ART, and 30% achieved viral suppression ( Figure 1).
Of 15,449 persons newly diagnosed with HIV in the 19 surveillance areas in 2011, 80% were linked to HIV medical care within 3 months. Linkage to care was lowest among persons aged 13-24 years (73%) and blacks (76%) ( Table 2).
Of the estimated 1.2 million persons living with HIV, an estimated 839,336 (70%) had not achieved viral suppression. Of these 839,336, an estimated 20% had never been diagnosed with HIV, 66% had been diagnosed but were not engaged in HIV medical care, 4% were in HIV medical care but had not been prescribed ART, and 10% had been prescribed ART but had not achieved viral suppression ( Figure 2).

Discussion
Of persons living with HIV in the United States in 2011, 30% achieved viral suppression. This percentage was relatively stable from 2009 (26%) to 2011 (4). Improvements are needed across the HIV care continuum to protect the health of persons living with HIV, reduce HIV transmission, and reach national prevention and care goals. The greatest opportunities for increasing the percentage of persons with a suppressed viral load are reducing undiagnosed HIV infections and increasing the percentage of persons living with HIV who are engaged in care.
HIV diagnosis is the entry point of the HIV care continuum. All adolescents and adults should be tested for HIV infection at least once. Pregnant women should be tested, including those presenting at labor with an unknown HIV status. Persons at increased risk for HIV infection should be tested at least annually, including men who have sex with men (MSM), persons who inject drugs, and persons presenting for sexually transmitted disease testing (7,8).
Persons living with HIV must receive HIV medical care to benefit from being prescribed ART, becoming virally suppressed, and receiving prevention counseling to reduce risk behaviors. Approximately 66% of persons who did not have a suppressed viral load were diagnosed with HIV but not engaged in HIV medical care. Thus, interventions that increase the likelihood that such persons will seek and receive ongoing medical care are essential. Strategies include strengths-based case management (i.e., encouraging patients to identify and use internal strengths and assets to overcome obstacles), provider notification systems, co-located medical and support services, clinic materials promoting engagement in care, clinic staff who have expertise serving affected subpopulations (e.g., youths and   gay men), and appointment scheduling (9). Patient navigation and outreach services might also be helpful (10).
To prevent deterioration of immune function, prolong life, and decrease transmission risk, all persons diagnosed with HIV should receive medical care and be offered ART as soon as possible after diagnosis with HIV infection, regardless of CD4+ count or HIV viral load (11). HIV medical care and treatment have multiple benefits. Most persons in HIV medical care are prescribed ART (92%) and achieve viral suppression (76%). Persons who are diagnosed with HIV at age 20 years and initiate ART immediately and consistently throughout their lives can expect to live an additional 51 years, which approaches the life expectancy of a person aged 20 years in the general population (1). Early ART has been shown to reduce the likelihood of sexual transmission of HIV by 96% (2). However, one in five newly diagnosed persons was not linked to care within 3 months, missing an important opportunity to receive early HIV treatment and care.
Outcomes along the HIV care continuum were associated with age. The lower percentages of younger people diagnosed, engaged in care, and on ART might reflect shorter duration of infection and less time for diagnosis. Further, the low percentage (13%) of persons aged 18-24 years achieving viral suppression is largely driven by the lower percentage diagnosed compared with other age groups. Although there were no significant differences in viral suppression by race/ethnicity, blacks had lower percentages than whites of being diagnosed and achieving viral suppression. Disparities along the HIV care continuum might reflect differences in access to and use of health care and treatment (12,13). Both targeted interventions and efforts to address underlying social determinants of health, such as increased access to health care and supportive services, could increase HIV diagnosis, engagement in care, ART, and viral suppression. These findings are subject to limitations. First, linkage to care is based on persons newly diagnosed in 2011 using data from only 19 areas with complete laboratory reporting so might not be representative of the United States as a whole. Second, engagement in care might be underestimated, because only persons receiving HIV medical care during January-April, 2011 were considered engaged in care. Weighted population estimates of persons on ART and virally suppressed were only calculated among persons engaged in care, so an underestimate of engagement in care might also lead to underestimates of ART and viral suppression. Third, percentages of persons on ART might also reflect guidelines in effect in 2011 recommending ART initiation for persons with CD4+ count <500 cells/µL, which were revised in 2012 and now recommend treatment for all persons with HIV regardless of immune status. Fourth, viral suppression was defined based on laboratory results at last test and might not indicate durable viral suppression. Fifth, the number of persons living with HIV infection was estimated using NHSS data and was calculated for persons aged ≥13 years. Medical Monitoring Project data include persons aged ≥18 years, so persons aged 13-17 years are included in the denominator, but not the numerator, for estimates of percentages engaged in care, on ART, and virally suppressed. However, there were fewer than 5,000 persons aged 13-17 State and local health departments, community-based organizations, and health care providers should work to reduce undiagnosed HIV infections and ensure that comprehensive services promoting linkage to, and engagement in, HIV medical care are available to all persons diagnosed with HIV. To support these efforts, CDC provides funding and technical assistance to reduce undiagnosed HIV infection, improve initial linkage and continued engagement in HIV medical care, increase viral suppression, and address disparities along the HIV care continuum. CDC is also working with state and local health departments to expand the use of HIV surveillance data in aggregate and on the individual level to improve engagement in HIV medical care and reduce viral load. The U.S. Department of Health and Human Services is supporting a range of projects to improve outcomes along the HIV care continuum, including research, Special Projects of National Significance, the Care and Prevention in the United States Demonstration Project, Partnerships for Care, Steps to Care, † and other innovative programs.
The findings in this report indicate that continued and intensified efforts are needed along the HIV care continuum. Only with success at each step in the continuum (i.e., diagnosing those with HIV, linking them to and engaging them in care, and ensuring they receive optimal treatment and prevention services) can the ultimate goals of improving health, reducing disparities, extending lives, and preventing further HIV transmission be achieved.